UDDEHOLM ORVAR 2 MICRODIZED

UDDEHOLM ORVAR 2 MICRODIZED
Properties
Physical data
Unless otherwise is indicated all specimens
were hardened 30 minutes at 1025°C (1875°F),
quenched in air and tempered 2 + 2 h at 610°C
(1130°F). The hardness were 45 ± 1 HRC.
Temperature 20°C 400°C 600°C
(68°F) (750°F) (1110°F)
Density
kg/m 3 7800 7700 7600
lbs/in 3 0.281 0.277 0.274
Modulus
of elasticity
N/mm 2 210 000 180 000 140 000
psi 30.5 x 10 6 26.1 x 10 6 20.3 x 10 6
Coefficient of
thermal expansion
per °C from 20°C – 12.6 x 10 -6 13.2 x 10 -6
per °F from 68°F – 7.0 x 10 -6 7.3 x 10 -6
Thermal
conductivity
W/m °C 25 29 30
Btu in/(ft 2 h°F) 176 204 211
Mechanical properties
Approximate tensile strength at room temperature.
Hardness 52 HRC 45 HRC
Tensile strength Rm
N/mm 2 1820 1420
kp/mm 2 185 145
psi 263 000 206 000
Heat treatment
Soft annealing
Protect the steel and heat through to 850°C
(1560°F). Then cool in the furnace at 10°C
(20°F) per hour to 650°C (1200°F), then freely
in air.
stress relieving
After rough machining the tool should be
heated through to 650°C (1200°F), holding
time 2 hours. Cool slowly to 500°C ( 930°F),
then freely in air.
Hardening
Pre-heating temperature: 600–850°C (1110–
1560°F), normally in two pre-heating steps.
Austenitizing temperature: 1020–1050°C (1870–
1920°F), normally 1020–1030°C (1870–
1885°F).
Temperature Soaking* time Hardness before
°C °F minutes tempering
1025 1875 30 53±2 HRC
1050 1920 15 54±2 HRC
* Soaking time = time at hardening temperature after the
tool is fully heated through
Protect the part against decarburization and
oxidation during hardening.
Yield point Rp0.2
N/mm 2 1520 1280
kp/mm 2 155 130
psi 220 000 185 000
APPROXIMATE STRENGTH
AT ELEVATED TEMPERATURES
Longitudinal direction.
psi Rm, Rp0.2
1000x MPa
290 2000
261 1800
232 1600
203 1400
174 1200
145 1000
116 800
87 600
58 400
29 200
Rp0.2
Rm
100 200 300 400 500 600 700 °C
210 390 570 750 930 1110 1290 °F
Testing temperature
4